Art and apparatus for cooling



Jan. 16, 1934. G. L E 1,943,315

ART AND APPARATUS FOR COOLING Filed Feb. 7, 1929 N {am I MQNTM BY 2-. 0&1

ATTORNEY Patented Jan. 16, 1934 UNITED STATES PATENT QFFECE 1,943,315 ART AND APPARATUS FOR CODLING Application February 7, 1929. Serial No. 338,113

17 Claims.

This invention relates to an art and apparatus for cooling, and more particularly for maintaining low temperatures in railway cars of the type generally known as refrigerator cars.

One of the objects of this invention is to provide a simple and practical art and apparatus for maintaining at low temperatures a car or other enclosure. Other objects are to provide cooling apparatus characterized by simplicity and compactness of construction, dependability of action and freedom from the necessity of skilled supervision under varying conditions of use. A more specific object is to provide a simple and effective means for using-a low temperature refrigerating substance such as solidified carbon dioxide. An-

other object is to provide a simple and effective means for distributing the cooling action. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combination of elements, arrangement of parts and in the several steps and relation and order of each of the same to one or more of the others, all as will be illustratively described herein and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing, in which are shown more or less diagrammatically the features of a selected embodiment of this invention:

The figure is a longitudinal section of a railway car.

Referring now to the drawing, there is shown a car body as 10, which may be of the usual construction. Within one end of this body and adjacent the end wall 11, is formed a refrigerating compartment as 12. The compartment 12 may have any'convenient form or location' and in the present embodiment this is provided by a parti tion as 13, extending cross-wise of the car. Within this compartment is mounted a receptacle 14., in the form of an annulus or hollow square having a central opening or fiue 15 extending therethrough. The outside wall 16 and thebottom wall 1'7 of this receptacle are preferably insulated whereas the top wall 18 and the inside wall 19 are preferably not insulated. r

In the portion 20 of the compartment 12 below the receptacle 14 there is mounted a coil or series of connected coils as 21, having connected thereto a heat absorbing coil 22. The ends of this coil 22 project through the wall 13 and such coil 22 may be arranged in any suitable manner within the body of the car. The coils 21 and 22 are filled with brine or other suitable'liquid having a very a low freezing point.

The central opening or flue 15 in the receptacle 14 may be partially or wholly closed at the bottom by doors or dampers as 24 of any suitable type to permit the regulation of the flow of air or gas through this passage into the chamber 0 20 and thus the cooling action on the liquid in the coils 21 and 22. These doors may be automatically controlled by the action of a thermostat 25 suitably located within the body of the car.

Vents as Z'Imay be provided in the walls of the 65 compartment 12 to permit the escape of gas from this compartment. Similar vents as 28 may be provided in or near the top of the receptacle 14 for the same purpose. A flue 29 is provided about the compartment 12 and this is open at the top and bottom to permit the circulation of gases in the manner which will be presently described.

Solidified carbon dioxide or carbonic acid resembling in appearance ordinary snow is packed in the receptacle 14. This substance evaporates without melting and such evaporation takes place spontaneously due to its taking up heat from the environment. The free carbon dioxide gas produced by evaporation passes through the vents 30 27 and mixes with the air in the compartment 12. This mixture of air and gas in the portion of the compartment above the receptacle and in the opening 15 becomes chilled mainly by radiation from the walls 18 and 19 and passes downwardly 3 in the opening to and through the chamber 20, thus passing about the coil or coils 21 therein and absorbing the heat from such coils. As this mixture becomes warm from passing about the coiis it enters the annular flue 29 at the bottom thereof as indicated by arrows and passes upwardly therein to the top of the chamber. Fromthence it passes over the receptacle 14 and again enters the opening 15 to repeat the cycle. Thus it will be observed that when, the doors 24 are open there is a continuous circulation of the gaseous medium within the chamber 12 and the coil or Cells 21 are subjected to refrigeration.

The chilled liquid in the coils 21 enters the heat absorbing coil 22 through the lower end and by thermosiphonic action passes upwardly in this coil, returning to the coils 21 at the top. In thus circulating through the coil 22 the liquid absorbs heat from the atmosphere in the body of the car and thus reduces its temperature. As the liquid approaches the upper end its temperature has been materially increased and it enters the upper portion of the coil 21 to be again cooled by the downward flow of the gaseous medium within the chamber 12. While means may be provided to accelerate the flow of the liquid through the coils 21 and 22. this is not necessary as the thermosiphonic action is generally sufficient.

The temperature of the fluid in the coil 22 and thus of the interior of the car body may be regulated by the doors or dampers 24 which may be adjusted either manually or automatically. A partial closing of these doors correspondingly restricts the downward flow of the gaseous medium through the opening or flue 15 and thus diminishes the cooling effect of the liquid in the coils 21. A total closing of the doors practically completely stops the circulation of such medium and very little if any cooling of the liquid in the coils 21 will occur, as there is very little radiation from the bottom wall 17 of the receptacle 14 due to the insulation there provided. This radiation may be further prevented, if deemed necessary, by providing insulation in or on the doors 24.

The reduction of the cooling action in the coils 21 causes the circulation therein to diminish and this will practically cease if the temperature in the chamber 12 below the receptacle 14 becomes substantially the same as that within the main portion of the car body. When automatic control of the temperature within the body of the car is desired, the doors or dampers 24 are constructed to be actuated by the thermostat 25 or other suitable means for the purpose. The automatic control mechanism is more or less conventionally illustrated in the drawing as the details of construction per se and their arrangement form no part of the present invention and any other suitable form or arrangement may be substituted therefor. In the construction shown, the expansive and contractive element 29 actuates a chain or cord 30 through the medium of a lever 31 and a bell crank 32. Adjustment of the parts is provided by a wing nut 33 on the rod 34 connected to the element 29. The chain or cord 30 is connected to the doors 24 by means of a bar 35 and links 36 and 37. When the temperature within the car body rises above or falls below that determined by the setting of the thermostat, this causes a corresponding opening or closing of the doors 24 and thus a substantially uniform temperature may be maintained within the body of the car.

The evaporation of the carbon dioxide within a closed receptacle would tend to create considerable pressure therein, but this is prevented in the present construction by vents 27 which per mit the escape of the gas from the receptacle 14 into the chamber 12. In the same manner the air or gaseous mixture within this chamber is permitted to escape through the vents 28, which may be provided with suitable check valves as 38 to prevent inflow of air.

It will thus be seen that there has been prcvided in this invention a practical art and apparatus for cooling a railway car or other compartment, and it .may be'noted that such cooling is effectively carried on to insure the maintenance of the desired low temperature in the car body during the various conditions of operation in transit to which the car may be subjected. A single filling of the receptacle will provide refrigeration for the car for a considerable period and such filling is an exceedingly simple operation as compared with icing.

No compressors or other operating mechanisms such as are required by other refrigerating systems are needed and the space required for such mechanisms is to a considerable extent made available for storage purposes, as the refrigerating compartment of the present apparatus may be relatively small. There is practically no mechanism to get out of order and this system is simple and economical to install. Such system of refrigeration has a further advantage over the icing method in that a lower temperature may be maintained. It will moreover be seen that the several objects hereinbefore noted as well as others, together with many advantages have been successfully achieved.

As many possible embodiments may be made of the mechanical features of the above invention, and as the art herein described might be varied, all without departing from the scope of the invention, it is to be understood that all matter herein set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In apparatus of the class described, in combination, a refrigerating chamber, an evaporator within said chamber to contain a solidified gas at atmospheric pressure and having a vent for the escape of gas into the chamber and a pipe line for circulating a liquid having a low temperature freezing point through said chamber within said chamber to contain a solidified gas,

vents in said evaporator communicating with said chamber, a pipe line for circulating a liquid having a low temperature freezing point through said chamber and the medium to be cooled, and fines for establishing circulation of the vented gas through said chamber and about said evaporator.

3. In apparatus of the class described, in combination, a refrigerating chamber provided with a vent communicating with the atmosphere, a substantially closed evaporator in said chamber to contain a low temperature refrigerating substance, a vent in said evaporator communicating with said chamber, a pipe line for circulating a liquid having a low temperature freezing point through said chamber and the medium to be cooled, and fines for estabiishing circulation of the gas vented from said evaporator within said chamber and about said evaporator and said pipe line.

4. In apparatus of the class described, in combination, a refrigerating chamber, a substantially closed receptacle fitting within said chamber adiacent the top thereof to contain a low temperature refrigerating substance and having an opening therethrough to provide communication between the portions of the chamber above and below said receptacle, a pipe line in said chamber beneath said receptacle to contain a liquid having a low temperature freezing point and conduct the same through the medium to be cooled and a flue outside said receptacle acting with said opening to establish by differential of temperature a circulation of a gaseous medium through said receptacle and about said piping.

5. In apparatus of the class described, in combination, a refrigerating chamber, a substantially closed receptacle fitting within said chamber to contain a low temperature refrigerating subfreezing point and conduct the same through the medium to be cooled, a flue outside said receptacle acting with the first mentioned flue to establish circulation of a gaseous medium within said chamber and about said receptacle and pipe line and means for regulating the flow of said gaseous medium.

6. In apparatus of the class described, in combination, a refrigerating chamber, a substantially closed receptacle located within said chamber adjacent the top thereof to contain a low temperature refrigerating substance, a flue extending through said receptacle to provide communication between the portions of the chamber above and below said receptacle, a coil in said chamber beneath said receptacle to contain a liquid having a low temperature freezing point, piping. connected to said coil to conduct said liquid through the medium to be cooled, a second flue acting with the first mentioned flue to establish circulation by diiferential of temperature of a gaseous medium through said receptacle and about said coil and a damper in one of said flues to control the circulation of said gaseous medium.

'7. In apparatus of the class described, in combination, a refrigerating chamber, a substantially closed receptacle fitting within said chamber ad jacent the top thereof to contain a low temperature refrigerating substance, a flue extending through said receptacle to provide communication between the portions of the chamber above and below said receptacle, a coil in saidchamber beneath said receptacle to-contain a liquid having a low temperature freezing point, piping connected to said coil to conduct said liquid through the medium to be cooled, a second flue acting with the first mentioned flue to establish circulation by differential of temperature of a gaseous medium through said receptacle and about said coil, a damper in one of said flues to controlthe circulation of said gaseous medium and means for automatically controlling said damper.

8. In cooling apparatus for railway cars, in combination, a refrigerating compartment formed Within the body of the car, an evaporator within said compartment to contain a low temperature substance, .a coil partially within said compartment and partially within the body of the car outside the compartment to contain a liquid having a low freezing point, and means for establishing circulation of a gaseous medium through said compartment and about said receptacle and coil to cool the liquid within said coil, said liquid being caused to circulate through said coil by thermosiphonic action.

9. The herein described art which consists in circulating an isolated refrigerating fluid through the lower part of a compartment and through a space which is out of communication with said compartment, evaporating a low temperature substance so that the resultant vapor refrigerant falls into thermal contact with said fluid and when warmed rises substantially to the top of said compartment, and controlling the falling of said vapor in accordance with the temperature of said space.

10. The herein described art which consists in placing a cooler including a low temperature substance within an enclosure in which is arranged an isolated liquid having a low freezing point, evaporating the substance to cool the liquid by circulating the gas downwardly over said liquid and thence upwardly by differential of temperature thereby surrounding said liquid with said gas, and conducting said liquid through the medownwardly over said coil and thence upwardly by differential of temperature in said enclosure, and circulating the cooled liquid by-thermosiphonic action in said coil and into a medium outside of said enclosure to be cooled.

12. The herein described art which consists in placing a low temperature substance within an enclosure, evaporating the substance therein, circulating a liquid into thermal contact with gas emanating from said substance, passing said liquid through a medium to be cooled, and control.- ling the evaporation of said substance and the flow of said evapor'ant to said liquid according to the temperature of said medium.

13. In apparatus of the class described, in combination, means forming a space whose temperature is to be regulated, a refrigerating compartment, an evaporator containing a low temperature substance within said compartment, means responsive to the temperature of said space for controlling the evaporation of said substance and the distribution of the gas emanating therefrom to all portions of said compartment, and piping means located within said compartment and in thermal contact with said space, said space being isolai)d and insulated from said gas, a portion of said piping means lying within said compart ment and adapted to be completely surrounded by said gas.

14. In apparatus of the class described, in combination, means forming a space whose temperature is to be regulated, a chamber thermally insulated from said space and divided into two sections, the upper section of said chamber including containing means for a solidified gas, a damper for controlling an opening between said sections, a continuous coil disposed within the lower section of said chamber and extending into said space, said coil containing a refrigerating liquid, and means responsive to the temperature of said space for controlling the operation of said damper whereby said damper opens when the temperature of said space rises above that preferred to allow sublimation of said solid and the passage of the resultant gas into thermal contact with said coil.

15. In apparatus of the class described, in combination, means forming a space whose temperature is to be regulated, a chamber thermally insulated from said space, containing means situated in said chamber and holding a solidified gas, a continuous coil disposed within said cham- 5 her and extending into said space, said coil containing a refrigerating fluid, and means responsive to the temperature of said space for controlling the direct connection between said containing means and said chamber to regulate the sublimation of said solid in accordance with the temperature requirements of said space.

16. In apparatus of the class described, in combination, means forming a space whose temperature is to be regulated, a chamber thermally insulated from said space, containing means disposed within said chamber substantially near the top thereof, said containing means holding a solidified gas, a continuous coil located in the lower part of said chamber below said containtinuous coil located in the lower part of said chamber below said containing means and extending into thermal contact with said space, said coil containing a low temperature heat absorbing fluid, means for controlling the flow of gas from said containing means to said chamber so that sublimation of said carbon dioxide may take place when said connection exists, and thermostatic means adapted to control said last-mentioned means to make said connection when the temperature of said space rises above that preferred.

GEORGE E. HULSE. 

